MathDB
All integers n ≥ (a − 1)(b − 1) can be written as n=ua+vb

Source: IMO LongList 1979 - P24

June 1, 2011
searchnumber theoryrelatively primenumber theory proposed

Problem Statement

Let aa and bb be coprime integers, greater than or equal to 11. Prove that all integers nn greater than or equal to (a1)(b1)(a - 1)(b - 1) can be written in the form: n=ua+vb,with(u,v)N×N.n = ua + vb, \qquad \text{with} (u, v) \in \mathbb N \times \mathbb N.